The invention relates to an apparatus suitable for protecting the spinneret face of a spinneret pack.
Synthetic fibers are generally produced by melt spinning thermo-plastic polymers, such as, for example, nylon, polypropylene, polyester, etc. In melt spinning synthetic fibers, the polymer used to produce the fibers is melted and pumped through an array of orifices in a plate usually called a spinneret. The melted polymer exiting the spinneret is then in the form of filaments or fibers which are rapidly cooled to a temperature below their melting point and then wound on a pirn or tube to form a package of yarn.
In order to produce high quality yarn it is important that the spinneret and the spinneret pack be in good condition. The spinneret is generally part of a unit known in the art as a pack, spin pack or spinneret pack. A spinneret pack comprises a housing, spinneret, mounting flange for mounting the spinneret to the outlet end of the housing, several screens of various sieve sizes and sand of various particle sizes. The screen and sand in the spinneret pack are used to strain the molten polymer and remove large particles before they reach the spinneret orifices. The pressure drop across a spinneret pack is usually monitored so that when a certain pressure drop is detected the spinneret pack is changed. Generally several spinneret packs are mounted on a beam which is actually a manifold through which the molten polymer travels from an extruder to several spinneret packs. Beams are generally constructed so that the spinneret packs are installed in the beam either from the top of the beam or from the bottom of the beam. Damage to spinnerets, such as a scratch or a dent in the extrusion face which distorts the shape of one or more orifices, is a common problem in fiber plants, and one that is becoming more and more expensive because of the complicated orifice configurations frequently employed. Most of the damage sustained by spinnerets occurs in the spinning area and especially when a spinneret pack is removed or installed in a beam. Although attempts have been made to eliminate or at least reduce such damage, little success has been realized.
An object of the invention is to eliminate or at least minimize damage to spinnerets.
Another object of the invention is to eliminate or at least minimize damage to spinnerets when the spinneret packs are removed or installed in a beam.
Another object of the invention is a method for reducing the number of damaged spinnerets.
Other objects, aspects and avantages of the present invention will be apparent to those skilled in the art after studying the specification, drawings and the appended claims.